Secrets of the 2,200-Pound Australian Marsupial Giant Revealed

Palorchestes azael, a marsupial tapir from the Pleistocene of Australia. (Nobu Tamura)

(CN) – A new study paints the picture of an extinct 2,200-pound marsupial tapir that roamed the Australian continent for the last 25 million years and was unlike any living mammal previously studied.

The Palorchestes azael or P. azael sported a tapir-like skull, hyper-retracted nasals, and strutted around with large scimitar-like claws and muscular limbs that it used to forage for food, according the study from Griffith University in Australia published Friday in the journal PLOS One.

The Palorchestidae family, or marsupial tapirs, were not the biggest creatures to call the Australian Outback home. That title belongs to the largest known marsupial Diprotodon, a hippopotamus-sized distant cousin of the wombat that was about 10 feet long and weighed about 6,100 pounds.

Researchers found that while the marsupial tapirs were not as big, their features were peculiar. The marsupial megafauna traveled on four legs but could also stand on its hind legs to perhaps reach food in trees.

Their arms were permanently fixed at roughly 100-degree angles, so they were always flexed and ready to gather food. While some body parts from the creature have yet to be discovered, estimates from this study provide the first descriptions of their morphology and unique anatomy.

According to the study, “it is clear that palorchestids moved and behaved in a way vastly different to their contemporaneous diprotodontid kin despite attaining comparable body sizes.”

These marsupial tapirs ranged from 220 pounds to around 2,200 pounds according to the study.

Marsupial tapirs, marsupial lions and giant wombats are in the same suborder as wombats and koalas that roam the Outback today, but characteristics of these extinct species, like P. azael, have been difficult to nail down, according to the study authors.

Ancient Australia was home to strange marsupial giants, some weighing over 2,200 lbs. (Hazel Richards, 2019)

Megafauna died off as the planet began to warm and human activity spread across the frontiers. The P. azael is estimated to have weighed more than one ton based on measurements of fossils that are much larger than other animals in the same genus.

“This study has allowed us for the first time to appreciate just how huge these mega-marsupial palorchestids were, while also providing the first comprehensive view of a strange limb anatomy unprecedented in the mammalian world,” according to the study’s authors.

The study further pulls back the curtain on this slender, muscular-clawed giant that could have been alive as recently as the end of the Ice Age.